During and after the construction of LILW disposal facilities, the decrease of groundwater head potential has been monitored. In addition, an increase of the electrical conductivity (EC) has been observed in several monitoring wells installed along the coastal coastline. Monitoring activity for groundwater head potential and hydrogeochemical properties is important to reduce the uncertainty in the evaluation of groundwater flow characteristics. However, the data observed in the monitoring wells are spatial point data, so there is a limit to the dimension. Several researchers evaluated groundwater head potential changes and seawater intrusion (SWI) potential for disposal sites using groundwater flow modeling. In case of groundwater flow modeling results for SWI, there is a spatial limit in directly comparing the EC observed in the monitoring wells with the modeling results. In a recent study, it was confirmed that the response of the long-range ground penetraiing radar (GPR) system was severely attenuated in the presence of saline groundwater. In order to reduce the spatial constraint of the groundwater monitoring wells for SWI, the characteristics of SWI within the disposal facility site by using the the results of a recent study of the long-range GPR system were investigated and evaluated in this study.

As a basic study to improve hooking ability of long line fishing gear, which is widely used around Jeju-do coast, the researcher performed hooking experiment of parrot fish by manufacturing and installing 7 kinds of model long line fishing gears, whose thickness of branch line are different and 8 kinds of model long line fishing gear, whose length of branch line are different, in indoor circular aquarium, which is installed for the model experiment of thickness and length of branch line that are various by fishing implement and improper. The hooking rate depending on thickness and length of branch line was calculated and the effect of thickness and length of branch line on hooking rate was analyzed. Its results are as follows. When branch line was thin and long, high hooking rate appeared. In the scope of value setting, the relationship between thickness (Bt) of branch line and total hooking rate (Thr) can be shown as following formula as. In the scope of value setting, the relationship between length (Bt) of branch line and total hooking rate (Bt) can be shown as Thr=-20.83Bt+26.04. Through Pearson correlation analysis, the coefficient of correlation between thickness of branch line and hooking rate was -0.718. Therefore it showed significance in 0.01 significance level. Through Pearson correlation analysis, the coefficient of correlation between length of branch line and hooking rate was 0.431. Therefore it showed significance in 0.01 significance level.

This paper is to investigate the effect of the immersion time in the traditional hairtail hand line for developing the fishing methods and the fishing gear in the coast of jeju. The operating of 32 times was made with each different immersion time of hairtail hand line, and the relations between the catch and the immersion time were examined. As the result, targeted species rate was over 98% of total catch. From about 800 seconds after casting, the hooking rate was decreased and the bite loss rate was increased, it seems to be made by the decreasing factors of predators including the cutting of branch lines etc. In addition, it was supposed that the hooking rate and the bait loss rate had a deep connection with feeding time zone. The level of the correlation coefficient of the bait loss rate according to the immersion time was 0.54 at p≤0.01, in the case of the hooking rate, 0.59 was chosen after about 800 seconds. The hooking rate and the bait loss rate according to the hook number were not irrelevant to the fish school layer. Additionally, it was assumed that the bait loss rate was related to the depth of water.

This experimental study was carried out to obtain the base data for saving the man power in the fishing operation of largehead hairtail hand line by using the continuous type hand line system with a rotary device which could make a main line move automatically. In order to solve the twists and entangling on the main line happened during operating test, the resistance board was suspended at the end of the main line at sea. As the result, there were no problems of tangling and so on due to up and down moving of a main line. According to the control of a fixed angle of guide roller, it was possible to prevent the main line to be separated from a side roller and a guide roller. In addition, PVC tube between a guide roller and a side roller enabled a main line to be moved smoothly without any entanglement.

A survey on the fishing gear for octopus drift-line fishing was done in Gangwon-do, Sacheon, Gyeongnam and Hokkaido, Japan, while a survey on the environments of fishing grounds used data from January to August from the Korea east coast farming forecast system of Donghae Fisheries Research and Development Institute. The present situation of fishing was examined with boats engaging in drift-line fishing from March to August in the coastal waters along Gangneung. The fishing tackle for octopus drift-line fishing was made manually, and the size, shape, and weight of the hook and number of shooting used vary according to the fishing time and region. Lead is used as the material for sinkers. As bait, pork fat with skin is mostly used in Gangwon-do. The temperature of the bottom water layer in the coastal fishing ground of Gangneung from April to June ranges from 3.2-12.4℃, which is the optimal temperature for octopuses. During July and August, the temperature ranges from 5.0-20.6℃. The maximum difference between day and night temperatures reached up to 9.2℃. Salinity is generally stable at 33.2-35.324.6%˚, which does not affect the inhabitation of octopuses. The octopus catch reached its peak from May to July, while most octopuses weighed less than 1 kg (76.7%). The results show that it is effective to carry out octopus drift-line fishing up to a depth of 40 meters; and that the maximum number of octopuses per line is obtained with an operation time of six hours.

낙지주낙 어장의 환경요인이 어획량에 미치는 영향을 조사하기 위하여 1997년 1월부터 7월까지 여수연안에서 풍향, 풍속, 물때별 및 조업 시각대별로 어획량을 각각 사하고 이들을 서로 비교 분석한 결과를 요약하면 다음과 같다. 1) 풍향별 어획량은 남동풍일 때 가장 많았고 북서풍일 때 가장 적었으며, 풍속별 어획량은 2일 때 가장 많았고 그보다 커질 경우는 감소하였다. 2) 물때별 단위 노력당 어획량은 15물에서 가장 많고 4물에서 가장 적으며, 조류가 차차 약해지는 11∼14물 사이의 어획량이 조류가 차차 강해지는 1∼4물 사이의 어획량보다 많았다. 3) 썰물과 밀물 때의 어획량은 간조에서 만조로 바뀐 후 1시간 동안의 구간, 즉 간조에서 물이 들기 시작한지 1시간 동안에 어획량이 가장 많았고, 썰물 시각대 보다는 밀물 시각대에 어획량이 비교적 많은 경향이었다.

낙지주낙 어장의 환경요인이 어획량에 미치는 영향을 조사하기 위하여 1997년 1월부터 7월까지 여수연안의 가막만 어장에서 수온, 염분 및 밀도등과 어획량을 각각 조사하고 이들을 서로 비교 분석한 결과를 요약하면 다음과 같다. 1) 낙지 주낙 어장에서 1~7월에 걸친 수온과 염분 및 현장밀도의 분포범위는 각각 4.1~23.6℃23.6, 31.7~34.5‰및 Σt, 21.30~27.81였고, 어획량은 이들 세 요인의 값이 각각 17~20℃, 33.0~33.5‰및 Σt 22.5~24.0 범위일 때 높아지는 경향을 보였다. 2) 낙지의 조업당 어척량은 10~16마리로서 비교적 낮은 편이며, 월별로는 1~2월에 적고, 3월부터 상승하기 시작하여 5~6월에 가장 높았다.

낙지 주낙 어장의 환경요인이 어획량에 미치는 영향을 조사하기 위하여 1997년 1월부터 7월까지 여수연안에서 수온, 염분, 밀도, 풍향, 풍속등과 어획량을 각각 조사하고 이들을 서로 비교 분석한 결과를 요약하면 다음과 같다. 1) 풍향별 어획량은 남동풍일 때 가장 많았고 북서풍일 때 가장 적었으며, 풍속별 어획량은 2일 때 가장 많았고 그보다 커질 경우는 감소하였다. 2) 물때별 단위 노력당 어획량은 15물에서 가장 많고 4물에서 가장 적으며. 조류가 차차 약해지는 11∼14물 사이의 어획량이 조류가 차차 강해지는 1∼4물 사이의 어획량보다 많았다. 3) 썰물과 밀물 때의 어획량은 간조에서 만조로 바뀐 후 1시간 동안의 구간, 즉 간조에서 물이 들기 시작한지 1시간 동안에 어획량이 가장 많았고. 썰물 시각대 보다는 밀물 시각대에 어획량이 비교적 많은 경향이었다

낙지 주낙 어장의 환경요인이 어획량에 미치는 영향을 조사하기 위하여 1997년 1월부터 7월까지 여수연안의 가막만 어장에서 수온, 염분 및 밀도 등과 어획량을 각각 조사하고 이들을 서로 비교 분석한 결과를 요약하면 다음과 같다. 1) 낙지 주낙 어장에서 I~7월에 걸친 수온과 염분 및 현장밀도의 분포범위는 각각 401~23. 6℃, 31.7~34.5‰ 및 Σt 21.30~27.81였고, 어획량은 이들 세 요인의 값이 각각 17~20℃, 33.0~33.5‰ 및 Σt 22.5~24.0 범위일 때 높아지는 경향이었다. 2) 낙지의 조업당 어획량은 10~16마리로서 비교적 낮은 편이며, 월별로는 1~2월에 적고, 3월부터 상승하기 시작하여 5~6월에 가장 높았다.

Mass mortalities of cultivated organisms have occurred frequently in Korean coastal waters causing enormous losses to cultivating industry. The preventive measures require continuous observation of farm environment and real-time provision of data. However, line hanging aquaculture farm are generally located far from monitoring buoys and has limitations on installation of heavy equipments. Substituting battery pack for solar panels and miniaturizing size of buoy, newly developed system can be attached to long line hanging aquaculture farm. This system could deliver measured data to users in real-time and contribute to damage mitigation and prevention from mass mortalities as well as finding their causes. The system was installed off Gijang and Yeongdeck in Korea, measuring and transmitting seawater temperature at the sea surface every 30 minutes. Short term variation of seawater temperature, less than one day, in Gijang from June to July 2009 corresponded tidal period of about 12 hours and long term variation seemed to be caused by cold water southeast coast of Korea, particularly northeast of Gijang. Seawater temperature differences between Gijang station and the other station that is about 500 m away from Gijang station were 1 ℃ on average. This fact indicates that it is need to be pay attention to use substitute data even if it is close to the station. Daily range of seawater temperature, one of crucial information to aquaculture, can be obtained from this system because temperature were measured every 30 minutes. Averages of daily range of temperature off Gijang and Yeongdeok during each observation periods were about 2.9 ℃ and 4.7 ℃ respectively. Dominant period of seawater temperature variation off Yeongdeok was one day with the lowest peak at 5 a.m. and the highest one at 5 p.m. generally, resulting from solar radiation.